I have read several posts from users on the forum who have the Logitech K400 wireless keyboard and seen varying levels of success being reported. The http://elinux.org/RPi_VerifiedPeripherals#USB_Keyboards wiki page lists this keyboard as working, but there is no mention of the touchpad. This guy: http://wenlong.wordpress.com/2011/10/30 ... ith-linux/ among others claims that the K400 works out of the box with Debian. My own keyboard works, but I get some sticky-keys and my touchpad doesn't work at all. When I try to reconfigure the keyboard, it comes up as a Generic 105-key, and (although there are a lot of logitech keyboards listed) the K400 is not an option I can choose.

If you have tried a K400 with your Pi, please post in this thread and vote in the poll to let the community know what your set up is, what level of success you've had, and if you had to work any Linux magic to achieve it. Then maybe we can come to some sort of consensus and update the Verified Peripherals page on eLinux, and avoid having people buying keyboards that aren't compatible. Perhaps we can also get a standard fix or set of instructions for owners of this popular keyboard.

I have almost the exact same set up, except for using an LG Android-based phone charger & have a Cisco/Linksys wifi dongle in addition to the keyboard receiver. While I do have occasional sticky key issues with the K400, the trackpad seems to work just fine in LXDE, all out of the box. Not sure about anything aside from LXDE, though.

The occasional sticky key but no tracked problems in Debian or RaspBMC. I thought I was at the end of its range (3m line of sight) but my Perixx 717 is worse. Perfect tracked but awful, like 15 mins to log in awful.

Both keyboard and track pad are working for me with LXDE. On occasion I would get a sticky key, press the 'k' once and multiple 'k's' would appear on screen. I turned my pi so the dongle faced me rather than facing away and all stickiness is gone. The keyboard and track pad also work in Quake3 although the touch pad is less than ideal for blowing away the baddies.

I have been using the K400 and have also tried my Logitech DInovo Mini keyboard. They both work. I do get sticky keys every so often. I may try the dongle on a USB powered hub to see if that keeps the keys from repeating.

Model: B
Distro: Debian “squeeze” 19-04-2012, using full 8GB class 10 SD card.
Power Source: Energizer XP8000 aslo acts as UPS, gives about 18 hours on battery. Can be plugged into 110 and used at the same time. Also has a 20 volt and 12 volt output.http://www.raspberrypi.org/phpBB3/viewt ... 119#p92119
Keyboard works: Yes, but with sticky keys may be due to range.
Touchpad works: Yes
Notes: Using a USB to serial PL2303 to X10 CM17A, software = heyu and bottlerocket for home automation.

Did anyone pair their keyboard with another computer first? Does the Logitech unifying receiver remember pairings across different computers or do you have to set it up for each system? I didn't pair mine before using the Pi, did any of you?

I have the K400 working out-of-the-box with debian6-19-04-2012 without any specific configuration of the RPi.

The "sticky keys" issue seems common, I am certainly experiencing that. However, I mostly see it only when using Midori. I am not sure if it is LXDE in general or Midori specifically, but the CPU usage often goes to 100% in Midori, so that may have something to do with it.

I have not seen the sticky key problem on the command line, and it seems responsive enough in a LXTerminal window too. It seems as if it sees the key-down but misses the key-up event. I think in fact it just as frequently misses a key-down, but that is far less annoying so perhaps underplayed as a symptom. I am going to try to partially work around it by setting the keyboard auto-repeat as slow as possible (when did anyone ever need that in any case!?).

The touch-pad works, including two-finger scrolling and double-tap gestures, the two-finger scrolling and mouse-buttons however seem somewhat unresponsive at times - probably the same issue as the sticky keys - perhaps the RPi is interfering with the RF signal and it is dropping data packets.

I am using it with an Edimax Nano WiFi, both plugged directly into the RPi, and both the same size - very neat; I only have a power and HDMI cable. It does not seem any more responsive with the WiFi removed however.

I did have some problems getting a power supply that worked reliably and in the end cut the connector off of a 4Amp USB hub PSU and spliced a micro-USB cable to it. Before I did that, the keyboard (and WiFi) problems were much worse. The K400 is rated at 100mA so is perhaps a bit marginal when plugged in directly. Has anyone tried it with a powered hub?

One more systematic problem I have found is that even with mouse speed and acceleration set to max in LXDE, it still takes endless stroking on the pad to get the mouse pointer across the screen.

Note that I initially testes the K400 on Windows where it was fine and did not exhibit any of these problems.

Similar to other people, my K400 generally works fine, but with the occasional sticky key. My guess is that this happens when the Pi is busy processing other things. Hopefully it will improve with future software updates.

My setup -

Model: B
Distro: Debian “squeeze” 19-04-2012, original
Power Source: The RS PSU that they sell on the Pi page.
Keyboard works: Yes, but with occasional sticky keys
Touchpad works: Yes, but occasionally have to click the buttons more than once.
Notes: Nothing in other USB socket.

My K400 was brand new straight out of the box and the tiny 'dongle' was plugged straight into my (also brand new) Raspberry Pi. Both keyboard and touch pad appear to work fine, and I only noticed one 'sticky' key occurrence, which could have been my fault anyway.

OS was standard 19-04-12 Debian "squeeze" on a 4GB SanDisk Class 4 SD card, and power came from my Samsung Galaxy II charger (5.02v). I also tried a Nokia one, which was a bit lower at 4.83v.

Display was a Toshiba 19" LCD TV with HDMI input and Midori was nice and clear.

The only change I made to the SD card was to add a config.txt file with the single line "hdmi_force_hotplug=1". I did have a bit of overscan initially, but this seemed to correct itself the second time I 'booted up' the Pi.

I am using a Logitech K400 as well, connected to a powered USB hub. The keyboard works fine with no sticky keys or lost touchpad input on a regular(Linux-based) PC, but sticky keys are extremely common on the Raspberry Pi to the point of the keyboard being almost completely unusable. It is so common that it is almost every other key.

What I've noticed is that it tends to happen a minute or two after plugging in the receiver or toggling the power switch on the keyboard.

These problems happen regardless whether or not the receiver is connected to the powered hub or a usb port on the Pi itself.

I already had a K400 and have been using it with my desktop for a while without any problems, and figured it would be a good option for the Pi, but when I plug it in it does nothing. Pi recognizes that there is a Logitech receiver plugged in, but nothing more than that. I just assumed that it didn't work with Pi, but now that I know others have it working I'd like to fix my issues.

I am using the same receiver that I was using with my PC, so it should be paired with it. The only thing I can think of was maybe using it on a Windows computer first may have messed it up to use it with Pi as well?

Tomorrow I am going to plug it into a Linux desktop and see if it works on there, any other advice?

Works for me in Debian & XBMC. Sometimes sticky keys (whether via hub or direct), so I've left it connected direct. Sometimes slow response / misses the 'mouse click' but this could be due to the CPU working overtime in these early software releases. So it's a 'yes it works' for the hardware and the device being correctly installed, but may need a few adjustments to make it a bit more user friendly.

Sorry to be off topic and mention Microsoft Wireless keyboard. Please see my post here:http://www.raspberrypi.org/phpBB3/viewt ... 014#p95771
It can take 5 attempts to login to Debian due to sticky keys.
With ArchLinux I have no sticky keys at all.
My conclusion is that it's a Debian problem, and I'd like to know where to file a formal bug report on the Debian configured for Raspberry Pi. It's worrying that standard USB devices like keyboards are problematic.

Did buy the K400 yesterday - and it does work out of the box with no problems.

Model: B
Distro: debian squeeze April 2012 / wheezy beta, raspbian pices R2
Power Source: NoName 2.1A USB-Charger from eBay
Keyboard works: in Terminal and in X
Touchpad works: in Terminal and in X
Notes:
- Monitor connected via HDMI
- Unifying receiver at the lower USB port of the RPi
- NO device in the upper Port (= No power hungry WLAN-USB-Dongle)
- Edimax WLAN-Bridge at the Ethernet Port
- Keyboard switched ON before the RPi
- Keyboard with german Layout (should we take a look at the revision of the keyboard?)